During the last several years applications have been developed and proposed that use integrated circuits (IC) or IC Cards for containing data and/or information with respect to the user. The main applications for IC cards include the following: electronic identity documents and passports, credit cards, health and identification cards and similar applications.
In particular, these documents contain biometric data for facial identification or for identification of fingerprints or for retinal scanning. The data is contained in a memory within the integrated circuit, and for safety, can be accessed through a protection system that comprises an access system using codes/electronic keys or other similar techniques.
The integrated circuit comprises a radio-frequency identifier or RFID (Radio Frequency IDentification) or an integrated element for a secure card or Smart Card, i.e., a low power chip that, when suitably supplied through electromagnetic waves, exchanges data and information with the reader circuit (Reader) or transceiver/transponder. The electromagnetic transmission between the integrated circuit and the transceiver/transponder circuit is obtained through at least two antennas.
An example of an IC card-reader system is shown in FIG. 1. In this case, the IC card 1 comprises a first integrated circuit or first IC 2 associated with a first antenna 3 that is external to it, and a reader 4 comprising a second integrated circuit or second IC 5 associated with a second antenna 6. Once supplied, the first IC 2 and the second IC 5 exchange information by using electromagnetic waves through wireless communication channels in a mode without contact, i.e., a contactless mode.
The antennas employed generally are of the Hertzian dipole type or of the magnetic dipole type, or other equivalent antenna type. The Hertzian dipole antennas usually have large sizes and have a moderate reading distance. They are generally external to the integrated circuit, and are connected by contact projections (or bumps) or conductive wires (wire bonds). For security IC card applications the use of magnetic dipole antennas is preferred since they provide communications at a reduced distance. This is due to a magnetic coupling therebetween.
Also, IC cards with embedded antennas, or an OCA (On-Chip Antenna) system, are known, wherein an antenna 3′ is integrated directly with the integrated circuit IC 2′, as shown in FIG. 2. This approach, although advantageous, has the drawback of substantially increasing the surface occupied in the wafer due to the integration of the antenna. This inevitably implies a reduction of the total number of integrated circuits present on the wafer, which consequently increases the total cost.
To reduce the surface being occupied, a known approach places the embedded antenna 3′ above the substrate that comprises the integrated circuit IC, thus obtaining an OCA, as shown in FIG. 3. It is also known, in particular, that IC cards with embedded antennas can use electromagnetic extensions 8 interposed between the integrated circuit 2′ and the reader circuit 4, as shown in FIG. 4. The electromagnetic extensions increase the operating distance or reading range between the integrated circuit 2′ and the reader circuit 4.
The electromagnetic extension 8 comprises at least two antennas 9, 10 connected through an interposed electronic circuit 11. The electromagnetic extension 8 concentrates the electromagnetic field, and thus the external electromagnetic energy on the integrated circuit IC with an embedded antenna 2′. Each antenna 9, 10 of the electromagnetic extension 8 can be a magnetic dipole or a Hertzian dipole, or other equivalent antenna type.
According to this approach, the electromagnetic extension is inserted in the container or package of the IC card, and has sizes that can be compared to the sizes of traditional IC cards. FIG. 5 shows an integrated circuit IC with an embedded antenna 2′ having an electromagnetic extension 8 formed with a resonant circuit LC 12, so that the electromagnetic extension 8 is resonant at a defined and suitable frequency or frequency range.
From a functional point of view, the integrated circuit IC with an embedded antenna 2′ and having the electromagnetic extension 8 of FIG. 5 is equivalent to the IC card with external antenna of FIG. 1. There is an advantage, however, in that the electromagnetic extension allows avoidance of an electrical connection through bumps or wire bonds between the integrated circuit and the external antenna.
The applications with IC cards provided with connection to a reader circuit of the wireless type, although advantageous, have the drawback of being vulnerable to remote attacks with illegitimate access to the data. In fact, during transmission of the data to the transceiver/transponder circuit or towards the IC card, possible remote attacks could overcome the mechanisms/barriers of protection and take the data contained therein. This data may then be used with potential, and even serious consequences, in respect to the privacy of the users.
Several approaches have been proposed for safeguarding the data contained in the IC cards. Naturally, the communications between the IC card and the transceiver/transponder circuit can occur through suitable protocols that allow, in some cases, cryptography of the data, at least partially, or to use access keys or protection systems. All this can also be extended to a generic chip or system coupled through the electromagnetic extension to a generic IC, SoC (System on Chip), SiP (System in Package) or to other similar type systems.
A known approach uses shields, such as, for example, casings or metallic and/or magnetic covers that allow protection of the IC card from possible attacks during transport. These shields, although advantageous under several aspects, make it more cumbersome to the IC card, and thus makes it more uncomfortable when transporting the IC cards. Moreover, after having removed the metallic and/or magnetic shield, for example, for validating one's own identity, the data is then vulnerable and can be intercepted by remote apparatuses.
In case there are two or more IC cards, being connected in a wireless manner to a single transceiver/transponder circuit, a suitable anticollision protocol avoids possible overlapping between the information and the messages as exchanged. These protocols often imply the use of communication modes of the TOM type (Time Division Multiplex) and/or FDM type (Frequency Division Multiplex) according to the cases and needs. The presence of suitable protection systems of the data is fundamental during the wireless transmission, i.e., during transmission through electromagnetic waves.
The technical problem underlying the present disclosure is that of providing a security system for protecting the wireless communications and the content of one integrated circuit in an efficient way with respect to possible remote interceptions. This is during the transmission/reception of the data and during the usual transport of the IC card. The IC card is to be compact and easy to manufacture while having structural and functional characteristics to allow the limits still affecting the protection systems realized according to the prior art to be overcome.
A further problem of the present disclosure is that of providing a secure integrated circuit card and a relative coupling element that is simple and reliable to allow protection of the data contained in the integrated circuit. In addition, secure wireless communications of the integrated circuit with a transceiver/transponder circuit having structural and functional characteristics is to be provided to allow the limits still affecting the cards according to the prior art to be overcome.
A further problem of the present disclosure is that of providing a method of secure wireless communications for one integrated circuit that is efficient and has structural and functional characteristics to allow the limits still affecting the methods of secure wireless communications according to the prior art to be overcome.